The India Meteorological Department (IMD) said Delhi, Haryana and Chandigarh will face a cold wave from January 4 to 6. A cold wave is declared when minimum temperatures fall 4.5°C to 6.5°C below the long-term average. IMD also predicted dense fog during night and morning hours over West Uttar Pradesh, Punjab, Chandigarh and Haryana between January 6 and 10.